There has been a long existing need to provide handicapped persons as well as the weak and infirm, such as post operative patients in hospital care, with toilet facilities for human waste excretion suitable for their use without assistance or minimal assistance from hospital or home nursing personnel. At present, many times two strong persons must physically assist an infirm person into and from a seated position on a toilet. This is a very difficult and awkward task. In addition, psychologically, the person being assisted normally would prefer to be as self-sufficient as possible in using the toilet. Too, difficult situations arise when hospital or nursing personnel are otherwise engaged or not available and the infirm person cannot use a toilet as desired.
It has been determined that psychologically, many elderly and failing persons tend to give up hope once they can no longer use a toilet without assistance from others. Thus, it is very desirable that a toilet facility be available which would offer maximum self-use by handicapped or infirm individuals.
Several such toilets have been proposed. Several related embodiments are described in U.S. Pat. No. 3,473,174 to Cool. The Cool devices function to lift their seats through a trajectory approximating the axis of articulation of knee joints. This forces a load upon a user's legs before they are straight, causing the user to have to exert himself to keep from sliding off the seat. Any such fixed hinge point devices will cause stress on a user to some extent. If a large radius is used, the elevated seat will be too horizontal in position, resulting in another high leg stress maneuver for the user to unseat himself.
Scissoring mechanisms are notoriously weak to side loading; the greater number of scissor members, the greater the weakness. Too, uncovered scissor members present obvious hazards to an unwary, careless or infirm user's body parts and clothing. It is extremely important that a movable toilet seat for the infirm provide stable support for a user at all times, and preferably allow its sanitary use at all times. The Cool seats do not provide stability for sanitary use at other than their full down positions. Spring loaded designs may assist healthy users, but offer little support or height control between seated or erect user positions.
The Cool designs furthermore do not provide ideal assistance to users having artificial knees and hip joints. Such users should not bend their artificial joints beyond 90.degree. because bending beyond 90.degree. can cause many artificial joints to uncouple. Use of the Cool mechanisms requires stress being placed on the leg members while the seat travels between its full down or seated and fully raised positions, causing any artificial joints to possibly be bent beyond 90.degree. under stress.
The Cool patent suggests no adjustment mechanism for users of differing height, and the electrical switch and motor required to operate the Cool device create a potential electrocution hazard.